Pass test suite.

* Add `travis.source_endpoint` meta (fixes many tests with hard
  expectations on `http://github.com` being in URL paths).
* Wrap `Ember.run.once` in a `Ember.run` (prevents test auto-run
  assertion).
* Fix expect counts for a couple tests.
Use standard Ember.Handlebars.registerBoundHelper.

No need for the custom Ember.registerBoundHelper implementation.
Controller#content -> Controller#model.
Update to Ember 1.8.1.
Do not run timers in testing.
Do not use globals to lookup views from template.
Keep elements fully within a single element.

{{if}} is implemented as an Ember.View (without an element), and
children must be valid DOM.
Remove view.state checks (in favor of _state).
Remove extra nesting level in integration test.
Use alias when appropriate.
Metamorph tags are no longer added, reducing the number of children.
No need to advanceReadiness (automatic with visit now).
Use container to lookup views (instead of globals).
Inject `config` into controllers.

Avoid deprecations from globals in template.
Merge pull request #308 from rwjblue/update-ember

Update to Ember 1.8.1.